1. Field of the Invention
The present invention relates to input devices whose output is changed based on a change in pressing stroke or in pressure when pressing an operating object, and in particular, to an input device in which power consumption in a no-operation state is reduced.
2. Description of the Related Art
Input devices for game machines and personal computers include those whose output is changed in analog form based on a change in pressing stroke or pressure.
In the input device described in Japanese Unexamined Patent Application Publication No. 2002-93274, a so-called “click rubber member”, such as a silicone rubber member, opposes an electrode provided on a base, and the click rubber member is supplied with pulse power. By operating a key top to allow the click rubber member to touch the electrode, electricity flows as an output. In addition, by pressing the click rubber member onto the electrode to elastically deform, the output is changed based on the amount of deformation.
In the above input device of the related art, when the click rubber member touches the electrode in response to the operation of the key top, the operation of the key top is recognized. Thus, the pulse power must be continuously supplied to the click rubber member even if the key top is not operated. In a state in which there is a distance between the click rubber member and the electrode, no power is consumed between the click rubber member and the electrode. However, continuous generation of pulse power as described above is wasteful power consumption.
By using plural electrodes and click rubber members of the above type, connecting the click rubber members in series, and extracting outputs from each midpoint between click rubber members, analog output which can be identified in positive and negative directions can be obtained. However, in this case, continuous supply of power to the click rubber members consumes power due to electrical resistance, so that wasteful power consumption occurs.